81371064 has 16 divisors (see below), whose sum is σ = 203427720. Its totient is φ = 27123680.

The previous prime is 81371051. The next prime is 81371077. The reversal of 81371064 is 46017318.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (81371051) and next prime (81371077).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1695207 + ... + 1695254.

Almost surely, 2^81371064 is an apocalyptic number.

It is an amenable number.

81371064 is an abundant number, since it is smaller than the sum of its proper divisors (122056656).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81371064 is a wasteful number, since it uses less digits than its factorization.

81371064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3390470 (or 3390466 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 81371064 is about 9020.5911114516. The cubic root of 81371064 is about 433.3345646250.

The spelling of 81371064 in words is "eighty-one million, three hundred seventy-one thousand, sixty-four".